Researchers saw substantial similarity between the two stem-cell types – pluripotent stem cells and embryonic stem cells, reported in a new study.
The study looked at four embryonic stem cells and four pluripotent or IPS cells, the proteins turned out to be 99 percent similar, says Joshua Coon, an associate professor of chemistry and biomolecular chemistry who directed the project.
“We looked at RNA, at proteins, and at structures on the proteins that help regulate their activity, and saw substantial similarity between the two stem-cell types,” he says.
Proteins are complex molecules made by cells for innumerable structural and chemical purposes, and the new study measured more than 6,000 individual proteins using highly accurate mass spectrometry, a technique that measures mass as the first step of identifying proteins.
“From a biological standpoint, what is novel is that this is the first proteomic comparison of embryonic stem cells and IPS cells,” says Phanstiel, referring to the study of which proteins a cell produces.
In essence, every cell in the body has the genes to make any protein the body might need, but cells make only the proteins that further their own biological role.
The new report, Coon says, suggests that embryonic stem cells and IPS cells are quite similar. According to some measurements, the protein production of an embryonic stem cell was closer to that of an IPS cell than to a second embryonic stem cell.
The study is not the last word in determining the similarity of the two types of pluripotent stem cells, says Coon, who worked with UW-Madison stem-cell pioneer James Thomson, on the project.
Because clinical uses of either type of stem cells will require that they be transformed into more specialized cells, researchers still need to know more about protein production after a stem cell is differentiated into, for example, a neuron or heart muscle cell.
Source: University of Wisconsin-Madison, USA